Polarimetry has long been used in many industrial and research-oriented applications such as organic chemistry, biology, pharmacology, and astronomy. More recently, polarimetry has proven to be highly valuable in a wide range of imaging applications using the measured intensities (radiances) and polarization of scenes. For example, polarimetric measurements can be used to obtain accurate and detailed characterizations for applications such as mineralogic mapping, urban growth monitoring, pollution assessment, and vegetation and environmental analysis, to name a few.
Unlike the traditional applications of polarimetry, in which the sampling and analysis are performed with the instrumentation and the research subject arranged in substantially stationary relationship relative to each other, more extensive polarimetric measurements often requires the scene information to be gathered from a moving platform, such as may be achieved by mounting and operating a polarimeter on an aircraft. The polarimeter is thus exposed to environmental conditions, such as temperature, pressure, humidity, contamination, etc., which may vary frequently during the data gathering operation. In order to obtain data which is consistently reliable in such applications, it is desirable to be able calibrate the polarimeter whenever changes in operating conditions occur, rather than only performing the calibrations in a laboratory setting preceding and/or following deployment into the field.